1. Field of the Invention
The invention is a ventilated molding which, when with or without a ventilated underlay, allows for moisture to be dissipated without damaging the flooring installed over the underlay.
2. Background of the Invention
Water vapor is emitted from concrete pads, often used as floors (or subfloors) in construction of homes, shopping malls, restaurants, retail establishments, warehouses, office buildings and other static structures. The water vapor can damage finished wood based flooring material. The water vapor can damage finished wood based flooring such as hardwood and laminate flooring that is installed over concrete sub floors. It can also damage other flooring products and promote the growth of mold and mildew.
When these floors are installed as a floating floor system over subfloors made of concrete or other materials, a vapor retarder or vapor barrier is often placed between the finished floor and the concrete sub floor to protect the finished flooring. The vapor retarder/barrier diverts most of the water vapor emitted from the concrete sub floor to the perimeter of the finished floor where it can disperse without damaging the finished flooring.
The vapor retarder/barrier is most frequently seen in the form of a polyethylene film, although it can be made of other materials as well. These retarders/barriers are typically constructed as a flat sheet of material with seams overlapped or taped. Some of these retarders/barriers are made with an irregular surface, such as raised features that allow easier movement of air and water vapor between the retarder/barrier and the concrete sub floor to the perimeter of the finished flooring.
All vapor retarders, as opposed to vapor barriers, allow the passage of some amount of water vapor. Small or larger amounts of water vapor can pass through the retarders as they are also diverting the majority of the water vapor to the perimeter of the finished flooring installation. When the building and the building site has been constructed to acceptable building codes, these vapor retarders often protect the finished flooring from normal water vapor emissions from concrete or other permeable sub floors; however, should the building's condition change, the building site change or is not constructed to protect the building from excessive moisture exposure, such as seasonal variations, poor repair or water drainage from the building site, then under these conditions the finished flooring can be damaged. Such damage can also occur when excessive water vapor is emitted from the concrete or other permeable sub floor. Water vapor passing through the vapor retarder, over time, will accumulate between the vapor retarder and the underside of the finished flooring, that water vapor is absorbed by the finished flooring causing the joints to swell and often causing a warped condition in flooring planks.
Barriers, in contrast, do not permit the passage of water vapor, but the tape used to joint these barriers together at their seams is often the weakest link. Over time such tapes, exposed to excessive moisture, can allow some passage of water vapor. In order to reduce excessive water vapor that could accumulate between vapor retarders and vapor barriers and the concrete sub floors, elaborate ventilation systems have been devised to vent the water vapor more quickly from beneath the retarder/barrier.
These ventilation systems use wall base molding and other materials. These systems are expensive to make and to install. Typically when a home is having its floor covering replaced all wall base molding usually remains fastened to the walls because it matches existing wall base throughout the home and replacing the wall base is not only expensive, it may also require refinishing the walls where the wall base is attached. When a finished molding is required at the edge of finished flooring where it meets the wall base, a quarter round or base shoe molding is typically installed. This molding is less expensive and easier to install than a wall base.